Yet the logic of its construction is still legible. The builders chose a shelf near the foot of a steep, north-facing slope above the Glanrastel River, then cut the structure slightly into the uphill side to the south and built the wall a little higher on the exposed northern face, a practical response to the slope and the prevailing weather that gives the ruin its slightly asymmetrical profile.

Drystone hut sites of this kind, built without mortar from locally gathered stone, are found across the uplands of south-west Kerry, though dating individual examples is rarely straightforward without excavation. The oval plan is among the oldest forms of vernacular building in Ireland, associated at various periods with seasonal settlement, transhumance, or the temporary sheltering of animals and people working hill ground. At Glanrastel, the structure measures roughly three metres east to west and just over two metres north to south, with wall remains still standing to around 0.4 metres. An arc of stones, extending from south-east to south-west, sits about a metre to the south of the hut; its function is unclear, though it may have formed a small windbreak or enclosure. Collapsed rubble has slid down the northern slope, tracing the outline of the original upper courses. Two further hut sites lie within thirty metres, one to the south and one to the west, suggesting this was not an isolated shelter but part of a small cluster, perhaps occupied together or in sequence across different seasons or generations.